JSantaniello

Hi All,

My 2012 E350 cabrio has the multicontour (I think that's what they are called) seats with the controls by the thigh. When I first start the car, I can hear and feel the air-pump working, and leaking when I manipulate the controls. After about 10 seconds it seems to give up and no further effect can be felt or heard while playing with the controls. Any tips or guestimates on how involved it is to fix these leaks? I'm hoping it is a hose junction or something relatively easy...


UPDATE: Just found excellent thread https://mbworld.org/forums/e-class-c...-deflates.html which answers my question: no, it's not an easy fix

Jaybird123

JS,

Did you decide not to pursue a fix, or still considering it? My new to me 2014 E550 coupe has a similar issue, whereby the lumbar inflates upon ignition but regularly deflates 5-10mins later. It’s quite...deflating! 😝 So it seems my pump does work, but either overheats or otherwise is triggered to cease function? As I age, I find lumbar support necessary and really would like to fix if possible

Mr. Toad

If the bolster inflates on ignition but subsequently drains of air, then it would seem that the problem is a leak in the bladder.

JSantaniello

Mine sounds like the leak is someplace by the passenger seat, and I have a hope that it is a hose or junction that may be somewhat accessible, and not an actual bladder as I am not up to dismantling the seats.

Mr. Toad

In that case, have a look at the bottom of the control pod (the part with the thumb wheels) between the seat and the console. If I recall correctly, you can pull the black plastic part up and see the air line connections underneath it.

JSantaniello

Excellent tip! After a little fiddling, it seems there is a leak at/near the rear-most driver-side thumb-wheel. Seems it can hold a limit degree of pressure in certain positions. That was determined just by playing with it; going to pull it apart tonight. Hopefully all will be sorted before weekend road-trip!

Mr. Toad

The rear one is the lumbar positioner (moves the protrusion up/down in the seatback).

JSantaniello

Finally got a replacement thumb-wheel unit in the post today and popped it into place, and it works like a charm. Thanks for the tip on pulling the pod up. Popped off without tools.

Cascd

May I know where did you get that replacement unit and do you have the part number? Thanks!

konigstiger

Seat control valve driver part # 0008007978, MBUSA passenger 0008007578 (markets w/out weight sensing 0008008078).

JSantaniello

I searched eBay for A0005254100 and bough the cleanest used one I could find.